峡部裂上位腰椎爆裂性骨折的治疗

[目的]探讨伴有峡部裂的腰椎爆裂性骨折的特点及其术式选择。[方法]对9例伴有峡部裂的上位腰椎爆裂性骨折，分别采用前路或后路减压植骨固定融合术、单纯经椎弓根固定术或加经伤椎椎弓根植骨的方式治疗。[结果]前路手术3例患者术后平均随访17．7个月，后路手术6例，内固定器取除术后平均随访15．8个月。全组病例峡部裂腰椎未发生滑脱征象。[结论]对于伴有峡部裂的腰椎爆裂性骨折，应根据骨折部位与峡部裂腰椎的位置关系选择不同的术式。     

青年战士腰椎峡部裂的分型与治疗

目的:根据青年战士腰椎峡部裂临床特点及影像学表现进行分型,根据不同分型采用不同手术方式,评价治疗效果及并发症。方法:回顾性分析2010年3月～2016年12月期间,我科收治的青年战士腰椎峡部裂患者326例。均为男性,年龄18-36岁,平均22.4±5.1岁。根据临床特点和影像学表现将所有病例分为3型,A型为单纯型峡部裂,无椎间盘突出及腰椎滑脱;B型为峡部裂伴有轻度椎间盘突出或Ⅰ度滑脱,无神经压迫症状及体征;C型为峡部裂合并Ⅰ度或Ⅱ度滑脱并椎间盘突出同时有神经压迫症状及体征。影像学检查:术前均进行腰椎正侧位、左右斜位、站立位全长正侧位X线片,腰椎CT及矢状位重建,腰椎MRI检查。腰椎X线片观察腰椎峡部裂位置及滑脱情况,腰椎CT明确峡部裂的程度及位置。腰椎MRI观察腰椎间盘突出及神经压迫情况。手术方法:A型或B型病例采用椎弓根钉固定,有滑脱进行复位,清理峡部,取髂骨峡部原位植骨。C型病例采用后路椎板减压,椎间盘切除,椎间植骨融合椎弓根螺钉内固定术。术后半年、1年、1年半门诊随访,采用视觉模拟评分(VAS)评价腰痛情况,Oswestry功能障碍指数(ODI)评价功能改善情况。术后半年,1年,1年半,2年及以后进行CT及矢状位重建判断峡部愈合情况。结果:A型和B型病例共305例,C型21例。283例得到随访,通过平均20.0±7.8个月的随访,VAS由术前的平均5.6±1.1分降至终末随访的1.1±0.3分,ODI由术前的平均25.2±3.2分降至末次随访的5.3±1.7分。术后半年复查CT发现,A和B型病例峡部裂愈合252例,愈合率91%(252/278),平均愈合时间12个月,愈合后再次手术取出内固定。椎间植骨病例无需取出内固定。结论:青年战士A、B型腰椎峡部裂病例采用椎弓根螺钉固定,峡部自体髂骨原位植骨融合率高,效果好,C型战士峡部裂则宜采用后路椎间植骨融合椎弓根螺钉内固定术。     

经椎板空心加压螺丝张力带治疗青年腰椎峡部裂

[目的]探讨应用经椎板空心螺丝张力带治疗青年峡部裂的疗效。[方法]2007年1月～2009年12月对15例(30侧)青年峡部裂患者进行峡部修整、峡部植骨融合、经椎板空心螺丝张力带复位固定和治疗。[结果]术后随访12～36个月,患者疼痛症状明显缓解,峡部裂处植骨骨性愈合,未见内固定松动、断裂。[结论]经椎板空心加压螺丝张力带是一种节段内治疗腰椎椎弓峡部裂安全、有效的内固定装置。     

Buck法螺钉固定联合椎板-横突植骨术治疗腰椎椎弓峡部裂

目的 探讨Buck法螺钉固定联合椎板-横突植骨术治疗腰椎椎弓峡部裂合并轻度腰椎滑脱的手术效果。方法 应用Buck法螺钉同定联合椎板-横突植骨融合,治疗10例合并Ⅰ～Ⅱ度腰椎滑脱的腰椎椎弓峡部断裂。结果随访8个月～4年,均达骨性融合,腰痛等症状缓解。结论Buck法螺钉固定联合椎板-横突植骨融合技术治疗合并Ⅰ～Ⅱ度以内滑脱的腰椎椎弓峡部裂,手术创伤小,对腰椎生理影响小,疗效可靠。     

横突-棘突间钢丝固定加植骨治疗腰椎峡部裂

腰椎峡部裂是椎弓峡部不连,多见于L4、L5节段.患者常有腰部疼痛,严重时可引起臀部及下肢放射痛,不少病人伴有腰椎滑脱,经保守治疗无效者需手术治疗.我们自1993年11月至1998年4月应用横突-棘突间钢丝固定加椎板、峡部植骨融合治疗无滑脱或滑脱小于Ⅰ度的腰椎峡部裂患者21例,取得满意疗效.     

椎弓根钉-椎板钩系统固定治疗单纯腰椎峡部裂

目的：观察应用椎弓根钉-椎板钩系统固定治疗单纯腰椎峡部裂的临床疗效。方法：自2002年6月以来．使用椎弓根钉-椎板钩系统治疗单纯腰椎峡部裂15例，均为男性，年龄19～36岁，平均27岁。L46例，L59例，均为双侧病变。所有患者均主诉明确的腰痛，持续6个月以上。术前腰痛疼痛评分（VAS）7．8分，采用后正中入路，暴露烈侧病灶，将峡部裂中的纤维瘢痕组织彻底清除，咬除骨残端硬化部分至出血为止，髂后上棘取骨行峡部裂局部植骨。安放病椎竹弓根螺钉及椎板钩，放置连杆后将同定系统锁紧。结果：术后疼痛症状明显缓解，VAS评分2．4分。随访12～26个月，峡部裂植骨均骨性愈合，末见骨不连及内同定断裂。结论：对于年轻的、单纯峡部裂患者可以采用椎弓根钉-椎板钩系统进行峡部修复，避免脊柱融合术：椎弓根钉-椎板钩系统是一种安全、有效的内同定装置。     

游离椎弓根峡部嵌入植骨术治疗合并椎间盘突出的腰椎弓峡部裂

目的：介绍一种治疗合并有椎间盘突出的腰椎椎弓峡部裂的手术方法。方法：先将患椎的后半部分游离取下并修整,待椎间盘切除、植骨床修整后,取髂骨块嵌入,再将后半部分回植,用螺丝钉贯穿固定,同时行横突椎板植骨。结果：本组治疗１３例,其中１１例随访１年以上,临床症状消失,峡部裂均融合,患椎滑脱无继续加重。结论：该术式操作简单,确实可靠,疗效理想。     

腰椎双椎峡部裂并单椎滑脱症的手术治疗

目的:探讨腰椎双椎峡部裂并单椎滑脱症的手术治疗方法.方法:2000年8月～2007年11月收治腰椎双椎峡部裂并单椎滑脱症患者11例,其中L4、L5双侧峡部裂伴L4椎体滑脱4例,伴L5椎体滑脱4例;L3、L4双侧峡部裂伴L3椎体滑脱1例,伴L4椎体滑脱2例.均行后路脊柱矫形固定器椎弓根钉棒系统(3D)复位固定、滑脱椎体全椎板切除减压和植骨融合术,其中滑脱节段行椎体间+横突间+峡部植骨7例,横突间+峡部植骨4例;峡部裂而无滑脱节段均行峡部+横突问植骨.根据侯树勋等的疗效评定标准评价疗效.结果:手术时间180～260min,平均210min:术中出血量600-1200ml,平均800ml.术后无神经根损伤及脑脊液漏等并发症.随访8～30个月,平均18个月,X线片和螺旋CT检查显示滑脱节段完全复位10例,大部分复位1例;已骨性融合10例,融合时间为5～15个月(平均7个月),1例8个月随访时尚未融合,以后失访;内固定无松动及折断.末次随访时疗效评定结果优8例,良2例,可1例.结论:应用后路脊柱矫形固定器椎弓根钉棒系统(3D)治疗腰椎双椎峡部裂并单椎滑脱症具有较好的复位和固定效果,配合滑脱椎体全椎板切除减压和后外侧融合或后外侧+椎间融合可取得较好的疗效.     

Wiltse微创入路治疗青年军人腰椎峡部裂

[目的]探讨Wiltse微创入路治疗青年军人腰椎峡部裂的临床疗效及体会。[方法]回顾性分析2011～2016年30例腰椎双侧峡部不连的青年军人,均为男性,年龄19～32岁,平均(23.72±3.69)岁。所有患者均采用Wiltse入路椎弓根螺钉-椎板钩、峡部植骨内固定的手术方式治疗。[结果] 30例患者术后3、6、12、24个月均获得随访。峡部裂植骨均骨性愈合,未发现断钉、脱钩等现象。所有患者术后腰痛症状明显缓解,术前及末次(术后2年)随访VAS评分分别为(6.70±1.32)、(1.54±0.62),术后VAS评分较术前明显改善,差异有统计学意义(P0.05)。根据Henderson疗效评定标准:优24例,良6例,优良率100%。[结论] Wiltse入路椎弓根螺钉-椎板钩加峡部植骨术进行峡部固定既可恢复椎弓的骨性连接,又可以更少的干扰正常组织结构、减轻组织破坏。在保守治疗无效的情况下,Wiltse入路椎弓根螺钉-椎板钩、峡部植骨术是一种行之有效的方法     

经椎板拉力螺丝钉治疗青年腰椎峡部裂

目的 探讨应用经椎板拉力螺丝钉复位固定、峡部植骨治疗青年峡部裂的疗效。方法 对26例青年峡部裂患者进行峡部修整、局部植骨、经椎板拉力螺丝钉复位固定。结果 26例随访6个月～6年,平均随访2．5年。患者下腰痛等症状完全消失,未出现螺钉断裂,仅有2例松动,复查腰椎X线片均显示峡部已骨性愈合。优21例;良5例。结论 经椎板拉力螺丝钉是一种节段性内固定治疗腰椎峡部裂确实有效的方法,简单易行,但应该严格掌握手术适应证。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.